Actors Jimmy O. Yang and Gemma Chan, two stars from the upcoming romantic comedy “Crazy Rich Asians,” joined the author of the best-selling book, Kevin Kwan, for a press day for the film in Boston in late July. The crew started their morning on a yacht docked behind the Boston Harbor Hotel and ended the day with a screening and party with VIPs. The guest list for the night, hosted by fashion maven and author Tonya Mezrich, included Boston Tweet’s Tom O’Keefe, the Citizens’ Housing and Planning Association’s Beyazmin Jimenez, Janet Wu, Mix 104.1’s Kennedy Elsey, and Maggie Lawler from the Four Seasons.